Louis eivet



Steam-Boiler.

No. 225,122. Patented Mar. 23,1880.

A 1 i 4A q www N PErERS, PHOTO-UTMCERAPMER, WASNINGICIN4 D c UNITEDSTATES PATENT OFFICE.

LOUIS RIVET, OF MINNEAPOLIS, MINNESOTA., ASSIGNOR OF TWOTHIRDS OF HISRIGHT TO NEWTON HARLOVV BOLTON, OF SAME PLAGE, AND SAMUEL WORKS SKINNER, OF ILION, NEW YORK.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 225,722, dated March23, 1880.

Application filed November E, 1879.

To all whom it may concern Be it known that I, LoUIs RIVET, ofMinneapolis,in the county of Hennepin and State of Minnesota, have madecertain new and useful Improvements in SteamBoilers, which improvementsare fully set forth in the following specification and accompanying drawings, in which- Figure l is a sectional elevation. Fig. 2 is 1o a planview, partially in section. Fig. 8 is a cross-section on the line .r .rof Fig. 1. Figs. 4 and 5 are views, reduced, of the large tube detached,showing variations in the methods of its construction.

This invention relates particularly to that class of horizontalsteam-boilers adapted to burn straw or other light fuel; and it conrsists in the employment of a horizontal tapering continuous liueprovided with a grate 2o at its larger end, having grids or lingers atthe rear end of the grate, in combination with converging return-finesaud a rear combustionchamber, so that a waterjacket may be formed aroundthe main flue and rear combustionchamber Without enlarging the shell ofthe boiler or reducing the grate-surface, as hereinafter set forth.

In the ordinary return-Hue boiler a large percentage of the effect ofthe heat is lost in 3o the combustion-chamber or smoke-jacket, ow-

ing to the thinness of its walls.

Many attempts have been made to utilize this heat by forming auxiliarywater-jackets, non-conducting coverings, &c., around thecombustion-chamber; but these have proved cumbersome and impracticableon portable boilers, as they add materially to the weight and expense.

To utilize this heretofore waste heat with- 4o out adding materially tothe expense or weight, or to reduce the grate-surface, is the object ofmy invention, which consists of the usual outer shell, A, inner largeflue, B, rear combustionchamber, E, and small returntlues aa.

The large flue B is made of the usual size at the front end, b, butcontracted toward the rear end, c, so that sufficient space may be leftfor a water-jacket, C, and the return-dues a' a withoutenlarging theouter shell, A, or 5o reducing the size of the grate D.

The rear combustion-chamber, E, is formed by the rear flue sheet on oneside and a straight cylindrical shell of less diameter than the outershell, by which a water-space is formed between them, thus forming awaterjacket around the same.

The tapering form of the main flue, the smaller end of which terminatesin the rear combustion-chamber, allows a greater area 6o for theinsertion of the return-tubes, and also a greater heating-surface forthe heat to impinge upon as it enters said return-tubes, thus producinga double advantage by its peculiar construction, as speciiied.

By this means I am enabled to materially increase the heating and watersurface of the boiler without altering the shape or size of the outershell or the grate.

The large iiue B may be tapered its entire 7o length, as shown in Figs.l and 2, or only a portion of its length, as shown in Figs. 4 and 5.

The grate D will be arranged in the usual manner in the forward end ofthe large flue B, and provided with lingers or bars r1, extending upwardnearly to the top of the flue, to serve as retarders toV the fuel andprevent it being drawn bodily through the iiues before the fire has hadtime to consume it. By 8o this means the total combustion of the fuel isinsured and all dan ger from sparks and cinders averted.

The `bars d may be set loosely in holes in the gratevbridge c, orsecured rigidly to or form 8 5 part of the grate-bars themselves. Theymay be made in any suitable lmanner to accomplish the desired result.

Having thus described my invention, what l claim as new, and desire tosecure by Let- 9o ters Patent, is-

The combination, in a horizontal steamboiler adapted to burn straw orother light fuel, o1" the main ilue B, tapering from its front to itsrear liuc-sheet, and provided at its front end with a grate havingupwardlyprojecting ngers or grid, with the outer shell, l my hand in thepresence of two subscribing A, extending beyond the said rearflue-sheet, l Witnesses. and with the inner shell of the rear eombusltion-chamber forming a water-jacket around LOUIS RIVET the same, andWith the return-tubes a, al1 Witnesses:

arranged to operate in the manner set forth. H. M. CURTIS,

In testimony whereof I have hereunto set U. N. WooDWARD.

